Well it was a great 2+ hours of listening to Thomas Proll. He apparently will be giving an abreviated version of this talk at the ARS fall meetings in St. Louis. He was in Ontario visiting Palatine. The talk was split into 2 parts, part 1 being a brief history of the company followed by a presentation of their breeding process. The second half of the talk he focused on the more recent (2004/05 onward) roses of theirs that have received the ADR designation. Hopefully my notes are correct.
So the breeding overview, he only talked about what they do for the garden roses. All crossing is done indoors starting April/May and going for about 6-7 wks. The parents are grown in 40L pots and they routinely have about a 30% turnover of parents each year. They use 400-500 pollen parents. I missed the number of seed parents, but there is 1400 pots of them with 2-3 plants/pot. They will make about 100,000 pollinations, representing ~2000 unique combinations, and resulting in 60-80,0000 hips (~800,000 seeds). Their average germination rate works out to about 50%.
They do not place the seeds in cold, rather they plant them in benches in their greenhouses and keep the temps between 2-4 C. Germination starts in Jan. Less than 10% of the seedlings will make it out of the greenhouse, those that do are immediately budded onto 3 rootstocks. This is generally around 10,0000 seedlings which are grown in their 3-plant field trial in year 2. In years 3-4, those that have survived selection (~1000 seedlings) are now grown in a 10-plant group field trial. Years 5-6, there are roughl;y 250 seedlings left and are grown in a 100-plant group field trial. By year 7 there are perhaps 10 seedlings left and they have 1000-plant groups of each of them. At this stage they will send about half of them to rose trials. By the mass propagation stage, years 8-10 they are down to 5-7 varieties and ~25,000 plants/yr of each. So they are looking at a 10 year window from crossing to commercial release of a named variety.
Breeding objectives - #1 goal is disease resistance, #2 is cold (frost) hardiness, #3 is heat tolerance, #4 is flowering abilities, #4 is flowering characteristics, #5 is growth characteristics, #6 ability to propagate on own roots, and #7 is cultivation in containers.
As I mentioned in the going native post, in 1990 Kordes stopped spraying for disease period. He showed a photo from the fields in 1990 and it was mostly just sticks, but there were a few plants that looked healthy. To contrast this he showed a recent photo of their trial fields and you would have a hard time picking out the sticks. The ADR trials are also no-spray, although I do not know when this practice was put into place.
So when he was talking about the more recent ADR lines I was trying to keep track of which ones he really stressed. Grand Amore, Eliza, Escimo, Golen Gate, Lions Fairy Tale, Kosmos, Pomponella, Jasmina (which is 1/2 rambler), Lupo (used for hip production) Aprikola was also heavily stressed. And at one point he did talk about Westerland being in the parentage of one of the roses, but for the life of me I do not remember which one.
Just as an aside, he spoke quite favorably about their competitor Noack’s efforts in developing disease resistant roses. Spoke about the difference in what the buying public in Germany and Europe wants vs. North America. Spoke about what Rosarians like/appreciate vs. the general buying public. And several times stressed the importance to the industry in developing roses that will shatter the perception that roses are difficult plants to grow.